Emergency response vehicles are often slowed down on their way to fires and accidents by other vehicles that do not move out of the way. Newer cars have better sound-proofing and drivers maybe listening to loud music which prevents them from hearing approaching sirens. Additionally, not all people know where to move to get out of the way of emergency vehicles. This condition (blocked roads) often slows first responders when time is of the essence. These circumstances may lead to accidents and collisions between emergency responders and other vehicles.
Additionally, conventionally lights and sirens have long been used to alert drivers of approaching EMS vehicles. Lately, with some vehicles, the sirens have been moved from the top of emergency trucks to bumper level in order to direct the associated sound and illumination toward other drivers. However, there are still deficiencies associated with these systems, such as drawbacks related to accidents and time.